Straight-edge for circular saws.



B. LAFLEUR.

STRAIGHT EDGE FOR CIRCULAR SAWS.

APPLIOATION FILED JUNE 15, 1909.

Patented Nov. 16, 1909.

UNITED STATES PATENT @FTQE.

STRAIGHT-EDGE FOR CIRCULAR SAWS.

Specification of Letters Patent.

Patented Nov. 16, 1909.

Application filed June 15, 1909. Serial No. 502,350.

To all whom it may concern:

Be it known that I, BARTHELEMY LAFLE UR, a citizen of the United States, residing at ilbbotsford, in the Province of British Columbia and Dominion of Canada, have invented a new and useful Straight-Edge for Circular Saws, of which the following is a specification.

The device herein described is intended as an improvement upon the straight edge for circular saws shown and described in Patent No. 838,551, issued, on the 18th day of December, 1906, to Barthelemy Lafieur.

The present improvements, forming the subject matter of this application, consist in an opaque plate adapted to be assembled with the other portions of the device in such a manner as to screen the eyes of the user when the device is in operation.

Another improvement consists in a giving to the resilient blade of the device, a tapering form, whereby it may be arranged to assume, along its fiducial edge, a more perfect curve.

With these and other objects in view, as will be hereinafter more fully explained, the invention consists in the novel construction and arrangement of parts hereinafter de scribed, delineated in the accompanying drawings, and particularly pointed out in that portion of this instrument wherein patentable novelty is claimed for certain distinctive and peculiar features of the device, it being understood, that, within the scope of what hereinafter is thus claimed, divers changes in the form, proportions, size, and minor details of the structure may be made, without departing from the spirit or sacrificing any of the advantages of the invention.

Similar numerals of reference are employed to denote corresponding parts throughout both figures of the drawings.

In the drawings :F igure 1 shows the rear of my invention in perspective; and Fig. is a transverse section thereof.

By way of explanation I will state that the improved saw-gage herein described, is adapted to be placed radially upon circular saws in order to ascertain whether or not the saw, having been hammered, has acquired the predetermined crown to which the ad justable blade of the device has been set.

In carrying out my invention, I provide primarily, a blade 1 fashioned from resilient material. This blade 1 is provided with a I centrally broadened portion from which the member tapers toward its ends. This taper which is given to the blade 1 causes it, under the action of means which willbe described hereinafter, to assume a more perfect and regular curve than any other form of which I am now aware. The blade 1 carries a plurality of backing members 2 which are longitudinally slotted to form jaws 1 adapted to straddle the blade 1. Rivets 3 are passed transversely through the jaws 1, and through the blade 1, whereby the backing members may be assembled with the blade.

The device further includes a stiff bar denoted by the numeral 5, and provided with openings, which are spaced from each other to conform to the space existing between the backing members 2. These openings are arranged to receive rods 7 which are threaded. The lower extremities of these rods 7 are rigidly assembled with the backing members 2 in any suitable manner. The threads 8 of the rods 7 carry upper clamp nuts 9 and lower clamp nuts 10 adapted to engage opposite sides of the bar 5.

An opaque plate 16 is provided, the upper edge of which is flush with the upper edge of the bar 5, with which it is assembled by means of rivets 17 or other suitable means. This-plate 16 extends downward past the adjacent edge of the blade 1, and, when the device is in use, prevents the light from passing between the blade 1 and the stifi bar 5, into the eyes of the observer, a contingency tending to prevent an accurate observation of the relation between the fiducial edge of the blade 1 and the saw which is being tested by the device.

The clamp nuts 9 and 10 in the present instance, are circular in form and are milled to provide a sufficient finger hold. The plate 16 is apertured to receive the lower clamp nuts 10, the upper clamp nuts 9 being adapted to bear upon the upper edge of the bar 5, and upon the upper edge of the plate 16. The plate 16 thus serves to reinforce the bar 5 against bending, and tends to enhance inaterially, the rigidity of the device.

The bar 5 and the plate 16 are provided with alined apertures 12 adapted to receive the longer arm of a square 11, the shorter arm of which extends downward into contact with the saw which is being tested, whereby the blade 1 may be held in a plane normal to the plane of the saw. The longer arm of the square 11 is slidably mounted in the aperture 12, and a set screw la is pro vided adapted to contact with the square 11, to prevent the accidental removal of the same from the device.

The rear face of the plate 16 is provided with a series of parallel, spaced, longitudinally extending lines 19, constituting graduations whereby the amount of crown given to the blade 1 may be ascertained.

Having thus described my invention what I claim as new and desire to protect by Letters Patent is 1. A device of the class described comprising a resilient blade; a rigid member arranged adjacent the blade; adjustable means i for crowning the blade connecting the rigid member and the blade; and an opaque member assembled with the rigid member and arranged to extend past the adjacent edge of the blade.

2. A device of the class described comprising a resilient blade; a rigid member arranged adjacent the blade; adjustable means for crowning the blade connecting the rigid member and the blade; and an opaque member assembled with the rigid member and arranged to extendpast the adjacent edge of the blade, the opaque member being graduated to indicate the crown of the blade.

3. A device of the class described comprising a resilient blade; threaded rods terminally assembled with the blade; a still bar having openings to receive the rods; upper and lower nuts mounted upon the rods and arranged to engage opposite sides of the bar; and an opaque member assembled with the rigid member and arranged to extend past the adjacent edge of the blade, the opaque member being provided with apertures to receive the lower of said nuts.

In testimony that I claim the foregoing as my own, I have hereto afiixed my signature in the presence of two witnesses.

BARTHELEMY LAFLEUR.

Vvitnesses E. A. BARRETT, B. E. MoCALLUM. 

